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CPM Calculator

Calculate cost per thousand impressions from spend and impressions.

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Free · No signup Live results Mobile-friendly

Last reviewed: 2026-11-09. Methodology: formulas use your inputs only — no hidden fees or market data APIs. Results are estimates for planning, not professional advice.

Basic

What it is & how to use it

CPM (cost per mille) is the cost of one thousand ad impressions. It is common for awareness and reach buying.

How to use the CPM Calculator

1) Enter total ad spend.
2) Enter impression count.
3) Read CPM live.
4) Compare placements only when formats and viewability rules are similar.

Intermediate

Formula & worked example

CPM = (Ad Spend ÷ Impressions) × 1000.
Worked example: $500 spend ÷ 100,000 impressions × 1000 = $5.00 CPM.

Advanced

Interpretation, edge cases & next steps

Cheap CPM can still waste budget if the audience is wrong.
Advanced: do not compare raw CPM across wildly different placements; translate to CPC/CPA when performance matters. See also CPC vs CPA models.
Planning estimate only.

Go deeper: CPM vs CPC vs CPA: What’s the Difference?

Frequently asked questions

CPM vs CPC?

CPM prices impressions; CPC prices clicks.

Why multiply by 1000?

CPM is defined per thousand impressions (mille).

Can impressions be lower than clicks?

Not with valid inputs — clicks cannot exceed impressions.

Is viewability included?

Only if your impression source already filters to viewable impressions.

When is CPM the right KPI?

Often for reach/awareness; use CPC/CPA for response and sales goals.

Deep guide

Read the full guide

Longer teaching, worked scenarios and mistakes — then jump back into this tool with example numbers.

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